In the agricultural industry, it is sometimes desirable to tow two agricultural implements behind a tow vehicle with a first agricultural implement towed directly behind the tow vehicle and a second agricultural implement towed behind and connected to the first agricultural implement. For example, it may be desirable to tow a cultivator through a field followed by an air cart or some other finishing implement towed behind the cultivator. If the agricultural implement being towed behind the cultivator is an air cart, it may be used to direct seed or fertilizer back to the cultivator so that the seed or fertilizer could be placed in the soil using the cultivator. In the case of other finishing tools, these can be used to further prepare the soil in the field.
For the cultivation of soil, for example, various styles of cultivators and harrows are employed. In cooler climates the most common types are the disc cultivator (sometimes called a disc harrow), the chain harrow, the tine harrow or spike harrow and the spring tine harrow. Chain harrows are often used for lighter work such as leveling the tilth or covering seed, while disc cultivators are typically used for heavy work, such as following plowing to break up the sod. Tine harrows are used to refine seed-bed condition before planting, to remove small weeds in growing crops and to loosen the inter-row soils to allow for water to soak into the subsoil. All three types can be used in one pass to prepare the soil for seeding. It is also common to use any combination of two harrows for a variety of tilling processes. Where harrowing provides a very fine tilth, or the soil is very light so that it might easily be wind-blown, a roller is often added as the last of the set. The disc cultivator is an implement used primarily to break up and smooth soil in preparation for planting and for the task of preparing soil for planting including tilling and leveling of fallow soil.
Cultivators and other agricultural implements have also increased in size over the years as tractors have increased in power resulting in some cultivators being quite large. Because of this many agricultural implements have sections that can fold up to reduce the size of the agricultural implement for transport, such as between fields or along roadways. These agricultural implements can be transformed between an operating position for use in a field and then “folded up” to make transport along roadways easier and safer.
However, this “folding” that some agricultural implements are capable of in order to ease transport presents challenges for connecting a second implement behind the first agricultural implement. The “folding” of the first agricultural implement can interfere with the connection to an implement being towed behind the cultivator.